Method for fabricating semiconductor device having titanium silicide film
In a method for producing a semiconductor device disclosed herein, a titanium film (131) is formed on a silicon layer and a titanium disilicide film (134) of a C49 structure is formed by the first rapid thermal annealing, followed by removing a titanium nitride film (132). The titanium disilicide film (134) thus formed is then subjected to phase transition to form titanium disilicide film (135a) of a C54 structure, and the titanium-excess titanium silicide film (133) is selectively removed by the second wet etching.
Latest NEC Corporation Patents:
- BASE STATION, TERMINAL APPARATUS, FIRST TERMINAL APPARATUS, METHOD, PROGRAM, RECORDING MEDIUM AND SYSTEM
- COMMUNICATION SYSTEM
- METHOD, DEVICE AND COMPUTER STORAGE MEDIUM OF COMMUNICATION
- METHOD OF ACCESS AND MOBILITY MANAGEMENT FUNCTION (AMF), METHOD OF NEXT GENERATION-RADIO ACCESS NETWORK (NG-RAN) NODE, METHOD OF USER EQUIPMENT (UE), AMF NG-RAN NODE AND UE
- ENCRYPTION KEY GENERATION
Claims
1. A method for producing a semiconductor device comprising the steps of: forming a field oxide film in an element separating region on the surface of a silicon substrate having a region of one conductivity type; forming a gate oxide film in an element forming region on the surface of said silicon substrate; forming a poly-crystal silicon film pattern in a region on the surface of said silicon substrate where a gate electrode is formed; forming a side-wall spacer consisting of an insulating film on the side wall of said poly-crystal silicon film pattern; forming a diffusion layer of an opposite conductivity type and self-aligned with said side-wall spacer on the surface of said region of one conductivity type; forming a titanium film over the surface of said field oxide film, said poly-crustal silicon film pattern, said diffusion layer, and said sidewall spacer; forming a titanium disilicide film of the C49 structure selectively on an upper surface of said poly-crystal silicon pattern and a surface of said diffusion layer of the opposite conductivity type by a first rapid thermal annealing in a nitrogen atmosphere; removing a titanium nitride film by a first wet etching; converting said titanium disilicide film of the C49 structure to a titanium disilicide film of the C54 structure by a second rapid thermal annealing; and selectively removing a titanium silicide film formed on the surface of said field oxide film and the surface of said side-wall spacer by a second wet etching after said converting step.
2. The method as claimed in claim 1, wherein said first wet etching is performed by a mixed solution of sulfuric acid and hydrogen peroxide to selectively remove said titanium nitride film.
3. The method as claimed in claim 1, wherein said second wet etching is performed by a mixed solution of ammonia water and hydrogen peroxide.
4. The method of claim 3, wherein the mixed solution of the second wet etching has an NH.sub.4 OH:H.sub.2 O.sub.2:H.sub.2 O ratio of 1:1:5.
5. The method of claim 3, wherein the first wet etching is performed using a mixed solution of ammonia water and hydrogen peroxide to selectively remove said titanium nitride film.
6. The method of claim 5, wherein the second wet etching is performed for 20 minutes.
7. The method of claim 5, wherein the second wet etching is performed at room temperature.
8. The method of claim 5, wherein the first wet etching is performed for 3-10 minutes.
9. The method of claim 5, wherein the mixed solution of the first wet etching has an NH.sub.4 OH:H.sub.2 O.sub.2:H.sub.2 O ratio of 1:1:5.
10. The method of claim 3, wherein the first wet etching is performed using a mixed solution of sulfuric acid and hydrogen peroxide to selectively remove said titanium nitride film.
11. The method of claim 10, wherein the second wet etching is performed for 30 minutes.
12. The method of claim 10, wherein the first wet etching is performed at 140.degree. C.
13. The method of claim 10, wherein the first wet etching is performed for 10-20 minutes.
14. The method of claim 10, wherein the mixed solution of the first wet etching has an H.sub.2 SO.sub.4:H.sub.2 O.sub.2 ratio of 5:1.
15. The method of claim 3, wherein the first wet etching is performed using a mixed solution of hydrochloric acid and hydrogen peroxide to selectively remove said titanium nitride film.
16. The method of claim 3, wherein the first wet etching is performed using a mixed solution of nitric acid and hydrogen peroxide to selectively remove said titanium nitride film.
17. The method of claim 3, wherein the first wet etching is performed using a mixed solution of phosphoric acid and hydrogen peroxide to selectively remove said titanium nitride film.
18. The method of claim 1, wherein the first rapid thermal annealing is performed at 690.degree. C.
19. The method of claim 1, wherein the first rapid thermal annealing is performed for approximately 30 seconds.
20. The method of claim 1, wherein the second rapid thermal annealing is performed at approximately 850.degree. C.
21. The method of claim 1, wherein the second rapid thermal annealing is performed for approximately 10 seconds.
| 4701349 | October 20, 1987 | Koyanagi et al. |
| 4788160 | November 29, 1988 | Havemann et al. |
| 4923822 | May 8, 1990 | Wang et al. |
| 5023201 | June 11, 1991 | Stanasolovich |
| 5043300 | August 27, 1991 | Nulman |
| 4-34933 | February 1992 | JPX |
- Krooshof, G.J.P. et al., Study of the rapid thermal nitridation and silicidation of Ti using elastic recoil detection.II.Ti on SiO.sub.2, Journal of Applied Physics, vol. 63, No. 10, May 15, 1988, pp. 5110-5114.
Type: Grant
Filed: Jan 23, 1997
Date of Patent: Jul 7, 1998
Assignee: NEC Corporation (Tokyo)
Inventors: Kunihiro Fujii (Tokyo), Hiroshi Ito (Tokyo)
Primary Examiner: John Niebling
Assistant Examiner: Thomas G. Bilodeau
Law Firm: Young & Thompson
Application Number: 8/785,279
International Classification: H01L 2128;
